title: Establishment of a simple Lactobacillus plantarum cell consortium for cellulase-xylanase synergistic interactions.
abstract: Lactobacillus plantarum is an attractive candidate for bioprocessing of lignocellulosic biomass due to its high metabolic variability, including its ability to ferment both pentoses and hexoses, as well as its high acid tolerance, a quality often utilized in industrial processes. This bacterium grows naturally on biomass; however, it lacks the inherent ability to deconstruct lignocellulosic substrates. As a first step toward engineering lignocellulose-converting lactobacilli, we have introduced genes coding for a GH6 cellulase and a GH11 xylanase from a highly active cellulolytic bacterium into L. plantarum. For this purpose, we employed the recently developed pSIP vectors for efficient secretion of heterologous proteins. Both enzymes were secreted by L. plantarum at levels estimated at 0.33 nM and 3.3 nM, for the cellulase and xylanase, respectively, in culture at an optical density at 600 nm (OD600) of 1. Transformed cells demonstrated the ability to degrade individually either cellulose or xylan and wheat straw. When mixed together to form a two-strain cell-based consortium secreting both cellulase and xylanase, they exhibited synergistic activity in the overall release of soluble sugar from wheat straw. This result paves the way toward metabolic harnessing of L. plantarum for novel biorefining applications, such as production of ethanol and polylactic acid directly from plant biomass.
authors.affiliation: Department of Biological Chemistry, The Weizmann Institute of Science, Rehovot, Israel.
authors.forename: Sarah
authors.initials: S
authors.lastname: Moraïs
authors.forename: Naama
authors.initials: N
authors.lastname: Shterzer
authors.forename: Inna Rozman
authors.initials: IR
authors.lastname: Grinberg
authors.forename: Geir
authors.initials: G
authors.lastname: Mathiesen
authors.forename: Vincent G H
authors.initials: VG
authors.lastname: Eijsink
authors.forename: Lars
authors.initials: L
authors.lastname: Axelsson
authors.forename: Raphael
authors.initials: R
authors.lastname: Lamed
authors.forename: Edward A
authors.initials: EA
authors.lastname: Bayer
authors.forename: Itzhak
authors.initials: I
authors.lastname: Mizrahi
mesh_terms: D044602:Cellulases / Q000235:genetics / Q000378:metabolism*; D048191:Lactiplantibacillus plantarum / Q000201:enzymology* / Q000235:genetics / Q000378:metabolism*; D008031:Lignin / Q000378:metabolism*; D060847:Metabolic Engineering / Q000379:methods; D059013:Microbial Consortia; D018547:Plant Stems / Q000737:chemistry; D010957:Plasmids; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D014908:Triticum / Q000737:chemistry; D014995:Xylosidases / Q000235:genetics / Q000378:metabolism*
chemical_list: D011994:Recombinant Proteins; C036909:lignocellulose; D008031:Lignin; D044602:Cellulases; D014995:Xylosidases